B16.47 Series A vs Series B: What's The Difference?
ASME B16.5 and ANSI B16.5 only cover sizes up to 24 inches. For bigger sizes, ASME B16.47 standard covers pipe flanges in sizes 26" through 60" and in pressure class ratings 75, 150, 300, 400, 600, and 900. Then, ASME B16.47 is further divided into ASME B16.47 Series A and ASME B16.47 Series B flanges for Blinds and Weldnecks.